2-34 PERIODIC MAINTENANCE
Periodic Maintenance Procedures
Be sure to remeasure the clearance after selecting
a shim according to the table. If the clearance is out
of the specified range, use the additional shim.
If there is no valve clearance, use a shim that is a few
sizes smaller, and remeasure the valve clearance.
When installing the shim, face the marked side toward the
valve lifter. At this time, apply engine oil to the shim or
the valve lifter to keep the shim in place during camshaft
Do not put shim stock under the shim. This may
cause the shim to pop out at high rpm, causing ex-
tensive engine damage.
Do not grind the shim. This may cause it to fracture,
causing extensive engine damage.
Apply engine oil to the valve lifter surface and install the
Install the camshafts (see Camshaft Installation in the En-
gine Top End chapter).
Recheck the valve clearance and readjust if necessary.
Install the removed parts (see appropriate chapters).
Air Suction System Damage Inspection
Right Side Cover (see Side Cover Removal in the Frame
Subthrottle Sensor Connector [A]
Air Switching Valve Hose [B]
Connect the subthrottle sensor connector.
Start the engine and run it at idle speed.
Plug the air switching valve hose end [A] with your finger
and feel vacuum pulsing in the hose.
If there is no vacuum pulsation, check the hose line for
leak. If there is no leak, check the air switching valve
(see Air Switching Valve Unit Test in the Electrical Sys-
tem chapter) or air suction valve (see Air Suction Valve
Inspection in the Engine Top End chapter).